1. Field of the Invention
The present invention relates to a cross roller bearing assembly that can be integrated into a mechanical translator table.
2. Background Information
Translation tables typically have a platform that can be moved relative to a stationary substrate. The table can provide a means to accurately move one object relative to another object. For example, in optical test benches, an optical component such as a focusing mirror, lens, etc. can be attached to the sliding platform of a translator. The platform may be attached to a micrometer that can be manipulated by an operator to vary the location of the optical component relative to the bench. The movement of the component may vary an optical characteristic such as the reflection angle, focus point, etc. of a light beam.
The translation table typically has a number of bearings located between the platform and the stationary substrate, to minimize friction between the two parts. The bearing assembly of a translation table typically includes a plurality of roller bearings located across the entire length of a bearing separator strip. Because of manufacturing tolerances it has been found that the roller bearings in the middle portion of the bearing separator strip may be larger than bearings located at the outer ends of the strip. This may cause the platform to teeter about the middle portion of the bearing assembly. Such a situation reduces the stiffness of the bearing assembly. The reduction in stiffness lowers the accuracy of the platform. The reduction in accuracy may be particularly critical when used in an optical bench where nanometer resolution is desired.
A bearing assembly that has a first pair of roller bearings located at a first end of a bearing separator strip and a second pair of roller bearings at a second end of the separator strip. The pairs of roller bearings are separated by a portion of the bearing separator strip that has no roller bearings.